this is actual art that was actually reviewed by someone, approved, and put on a book cover. Harry Potter of all things. Its not like this was done because of a small budget.

you can make it, even with shitty art. you just have to actually look for those jobs, make a portfolio and do the boring and annoying task of networking and advertising your services. but just because you "make it" doesn't mean your art isn't utter trash. so ask yourself what is more important for you: making good art, or selling it. because those things aren't synonymous.